Objective. To study the iodine supply of children on a vegetarian diet and to evaluate the effectiveness of iodized salt for the prevention of iodine deficiency. Methods. 65 vegetarian children( from 7 to 11 years) were examined. The control group included 40 healthy children of the same age which had no any dietary restrictions. All children lived in the Donetsk Republic. The study of iodine supply was carried out by determining the median of ioduria in the group. Taking into account the identified changes in the iodine supply of children of the surveyed groups, we prescribed them the prevention of iodine deficiency using iodised salt. The effectiveness was evaluated in 6 months. Results. In the main group, the median iodine was 68.4 μg/L, which is mild iodine deficiency. At the same time, 33.9% of children of the main group had a level of ioduria <50 μg / l. In the control group, the median iodine was 97.1 μg/L. Ioduria <50 μg/L had 25.0% of children. In 6 months from the beginning of iodised salt use in the main group, the median iodine was 107.8 μg/L, which is normal iodine supply, and the proportion of children with an iodine concentration in the urine <50 μg/L was 16.9%. In turn, in the control group, after preventive use, the median iodine was 122.5 μg/L, and the proportion of children with ioduria <50 μg/L decreased to 12.5%. Conclusion. The children living in the Donbass have a mild iodine deficiency. Vegetarianism without the use of iodised salt leads to an even more pronounced iodine deficiency. The received data allows to consider that vegetarian children have a risk of iodine deficiency. Regular iodized salt use is an effective prevention of iodine deficiency not only in traditionally fed children, but also in vegetarian children. Key words: vegetarianism, iodine, iodine deficiency, children, iodised salt